Plastic eavestrough systems are normally based on a solvent seal where the eavestrough is permanently secured to the fitting or are based on a dynamic seal where the eavestrough is free to move within the fitting. In systems having a dynamic seal, resilient sealing members are adhered to the fitting. The most common method of securing of these seals is to mold the gasket member directly on the plastic fitting. With solvent base systems, the eavestrough is permanently secured to the fitting by means of a solvent, such that a permanent bond between the eavestrough and the fitting occurs. Unfortunately, with plastic eavestrough fittings, thermal expansion of the eavestrough can be considerable and expansion and contraction must be taken into account, based on the extremes between summer and winter conditions. In a dynamic seal system, such expansion is accommodated due to the fitting which can accept the movement of the eavestrough, however, in a solvent system, separate expansion and contraction units must be inserted. Failure to insert such expansion and contraction units in a solvent base eavestrough system will result in breaking of certain solvent bonds and resulting in leaking of the joints.
The use of nonsymmetrical eavestroughing, such as a "K" style eavestrough when manufactured in plastic, has used a solvent based system, as dynamic seals have generally been confined to symmetrical type eavestrough systems.
There remains a need to provide an effective system for securing of nonsymmetrical eavestroughing by means other than a solvent seal.